Portable battery powered communication devices, such as radios and cellular telephones, continue to provide additional features to the consumer. To this end, designers have had to integrate and miniaturize an increasing number of circuits and features within the device. Recently, designers have even started incorporating radio features, in the form of application specific modules, within the battery pack. These application specific modules are manually turned on and off via an on/off switch. The on/off switch is not typically available to the end-consumer but is usually set at the factory or by a service shop.
The ability to upgrade a portable radio without taking the radio to a service shop for programming and without additional interface hardware is highly desirable. Adding radio functionality to the battery pack poses several challenges, one being that the radio electronics located in the battery pack must be turned off when the radio is turned off, so as not to drain the battery cell(s). While an additional contact can be used to provide this on/off capability, older existing radios can not be retrofitted and newer radios require a larger interface connector thereby increasing parts count and cost.
Accordingly, it would be desirable to have a battery pack with a simplified on/off control of an in-battery application module.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.